Kitaibelia vol. 7 – no. 2. (2002) p.109-117.
Taxonómiai vizsgálatok a hazai molyhos tölgy alakkörön (Quercus pubescens s. l.) mikromorfológiai bélyegek segítségével
The trichomes of leaves and shoots were examined at 586 Quercus pubescens trees from 77 stands according to the method of Aas (1998). The most important results are as follows.
The micromorphological variation of Q. pubescens populations in Hungary is similar to that of in the Mediterranean region.
The introgressive hybridization between Q. pubescens and Q. petraea is much higher than formerly presumed in the Hungarian Mountain Range.
In the South-Transdanubian populations the proportion of samples with stellate trichomes is much below the avarage. It can be explained by the fact that the submediterranean precipitation effect grows to South (Borhidi, 1991).
The ratio of samples with stellate trichomes is low in the samples from the Great Hungarian Plain too. At the same time the variety of pilosity-types is the highest just in this region. It can be explained by the absence of Q. petraea in most of the stands, while Q. pubescens and Q. robur transitional forms appear in the populations.
The introgressive hybridization contributes to the remarkable variety of Q. pubescens.
In the Hungarian Mountain Range the rate of the transitional forms between Q. pubescens and Q. petraea is significantly higher on non-basic sites than on basic ones. We can establish that the extremely dry and acidic sites are favourable for hybridization, that is the introgression between the species can play an important role in their ecological adaptation.